To allow for re-injection of stage-2 faults on stage-1 page-table walks
due to either a missing or read-only memslot, move the triage logic out
of io_mem_abort() and into kvm_handle_guest_abort(), where these aborts
can be handled before anything else.
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Quentin Perret <qperret@xxxxxxxxxx>
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
---
arch/arm64/kvm/mmio.c | 6 ------
arch/arm64/kvm/mmu.c | 13 ++++++++++++-
2 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/kvm/mmio.c b/arch/arm64/kvm/mmio.c
index 4e0366759726..58de2ae4f6bb 100644
--- a/arch/arm64/kvm/mmio.c
+++ b/arch/arm64/kvm/mmio.c
@@ -145,12 +145,6 @@ int io_mem_abort(struct kvm_vcpu *vcpu, struct kvm_run *run,
return -ENOSYS;
}
- /* Page table accesses IO mem: tell guest to fix its TTBR */
- if (kvm_vcpu_dabt_iss1tw(vcpu)) {
- kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));
- return 1;
- }
-
/*
* Prepare MMIO operation. First decode the syndrome data we get
* from the CPU. Then try if some in-kernel emulation feels
diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c
index 4150bce3d0b6..9f5fde1243d4 100644
--- a/arch/arm64/kvm/mmu.c
+++ b/arch/arm64/kvm/mmu.c
@@ -2105,12 +2105,23 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
write_fault = kvm_is_write_fault(vcpu);
if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
+ /*
+ * The guest has put either its instructions or its page-tables
+ * somewhere it shouldn't have. Userspace won't be able to do
+ * anything about this (there's no syndrome for a start), so
+ * re-inject the abort back into the guest.
+ */
if (is_iabt) {
- /* Prefetch Abort on I/O address */
ret = -ENOEXEC;
goto out;
}
+ if (kvm_vcpu_dabt_iss1tw(vcpu)) {
+ kvm_inject_dabt(vcpu, kvm_vcpu_get_hfar(vcpu));
+ ret = 1;
+ goto out_unlock;
+ }
+
/*
* Check for a cache maintenance operation. Since we
* ended-up here, we know it is outside of any memory
--
2.28.0.rc0.142.g3c755180ce-goog
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